摘要:
The process of this invention for preparing 2,6-naphthalene-dicarboxylic acid comprises a reaction step (Step A) wherein 2,6-naphthalene-dicarboxylic acid potassium salts consisting of 2,6-naphthalene-dicarboxylic acid dipotassium salt and/or 2,6-naphthalene-dicarboxylic acid monopotassium salt are allowed to react with benzene-carboxylic acids in the presence of water to yield 2,6-naphthalene-dicarboxylic acid and benzene-carboxylic acid potassium salts and a separation step (Step B) wherein the crystallized 2,6-naphthalene-dicarboxylic acid is separated from the benzene-carboxylic acid potassium salts dissolved in the aqueous solution and provides 2,6-naphthalene-dicarboxylic acid, useful as raw material for polymers, at low cost on a commerical scale with recycle of potassium.
摘要:
A process for the preparation of aromatic carboxylic acids or their salts comprises heating carboxyl-free aromatic compounds and aromatic carboxylic acid salts whose basic structures differ from those of the aromatic compounds, or heating polycyclic aromatic compounds with three or more rings and monocyclic or bicyclic aromatic carboxylic acid salts, under carbon dioxide pressure in the presence of one or more metal compounds selected from group (a) of compounds of zinc, cadmium, and thallium and one or more compounds selected from group (b) of compounds of cesium, Group II metals, And Group IIIa metals to effect the intermolecular transfer of the carboxyl groups.
摘要:
This invention relates to a process for preparing indan derivatives and comprises a process for preparing cis-1-amino-2-indanol by treating (.+-.)indan-1,2-diol and/or its 2-formate derivative with specific microbes to give optically active 2-hydroxy-1-indanone, converting the optically active 2-hydroxy-1-indanone to its oxime, and treating the oxime with hydrogen or a hydrogen donor in the presence of a heterogeneous hydrogenation catalyst, a process for preparing optically active 2-hydroxy-1-indanone and/or optically active indan-1,2-diol by treating (.+-.)indan-1,2-diol and/or its 2-formate derivative with specific microbes, and a process for preparing cis-1-amino-2-indanol by treating the oxime of 2-hydroxy-1-indanone with hydrogen or a hydrogen donor in the presence of a heterogeneous hydrogenation catalyst.
摘要:
Disclosed is a process for the preparation of a naphthalene-2,6-dicarboxylic acid dialkali metal salt which comprises heating an alkali metal salt of naphthoic acid and/or a dialkali metal salt of naphthalene-dicarboxylic acid under pressure with carbon dioxide gas in the presence of a catalyst, wherein an aprotic polycyclic aromatic compound having 2 or 3 rings is used as a reaction medium. Naphthalene-2,6-dicarboxylic acid dialkali metal salt can be obtained in high yield and selectivity with a good reproducibility of the reaction.
摘要:
Novel .alpha.-thio-alkanoic acid derivatives and a process for their preparation. These novel compounds can be easily converted to useful medicines.
摘要:
A manufacturing method is described for the preparation of optically active 1-aromatic-group-substituted-1-alkanones characterized in that an optically active alkane acid halide is allowed to react with an aromatic compound in the presence of a Lewis acid. The optically active 1-aromatic-group-substituted-1-alkanones are useful intermediates in the preparation of optically active alpha-arylalkanoic acids, which are useful as pharmaceutical, e.g. anti-inflammatory, analgesic and anti-pyretic, agents and as insecticidal agents.
摘要:
A manufacturing method is described for the preparation of optically active 1-(6-methoxy-2-naphthyl)-2-(alkoxycarbonyl)amino-1-propanone, its derivatives and their halo analogs. The optically active 1-(6-methoxy-2-naphthyl)-2-(alkoxycarbonyl)amino-1-propanone, its derivatives and their halo analogs are useful intermediates in the preparation of 2-(6-methoxy-2-naphthyl)propionic acid, which is useful as pharmaceutical, e.g. antiinflammatory, analgesic and anti-pyretic agents.
摘要:
The present invention provides .alpha.-methylthio-.alpha.-(p-phthalimidophenyl)-propionic acid and its esters of the formula: ##STR1## wherein R' represents H or C.sub.1 -C.sub.4 alkyl. The subject compounds are useful as intermediates e.g. for Indoprofen.
摘要:
An alpha-thio-alpha-aryl-substituted alkanonitrile of the general formula ##STR1## wherein Ar represents an aromatic group, R represents a hydrogen atom or an alkyl group, R.sup.1 represents an alkyl group or an aromatic group, and Y represents an oxygen atom or a carbonyl group. The above compound can be prepared by reacting an alpha-aryl-substituted-alpha-thio-acetonitrile of the general formula ##STR2## wherein Ar, Y and R.sup.1 are as defined above, with an alkylating agent in the presence of a strong base. This compound is useful as an intermediate for producing an alpha-aryl-substituted alkane-carboxylic acid of the general formula ##STR3## wherein Ar, Y and R.sup.1 are as defined above.
摘要:
Novel .alpha.-thio-alkanoic acid derivatives and a process for their preparation. These novel compounds can be easily converted to useful medicines.